Punch mechanism for perforating film



June 19, 1962 N. n. NYE 3,039,713

PUNCH MECHANISM FOR PERFORATING FILM Filed Feb. 13, 1959 70 III/III INVENTOR. NORMAN H.NYE

ATTYS.

United States Patent f 3,039,713 PUNCH MECHANISM FOR PERFORATING FILM Norman H. Nye, Cuyahoga Falls, Ohio, assignor to Pen-Mac-Nye Company, Akron, Ohio, a corporation of Ohio Filed Feb. 13, 1959, Ser. No. 793,181 Claims. (Cl. 242-568) This invention relates to apparatus for perforating films, such as plastic, paper, and the like, to adapt it to certain packaging or other operations.

It is the general object of the invention to provide film perforating apparatus characterized by low initial and maintenance costs, ease and rapidity of operation, and by uniformity of product.

Another object of the invention is the provision of apparatus for perforating thin films, such as cellophane, vinyl, polyethylene, paper and the like, and wherein the film is perforated over the desired portion of its width as the film moves rapidly from a let-off roll to a windup roll.

Another object of the invention is to provide mechanism of the type described wherein the actual perforating operations are performed by punches driven with an impact against the tensioned film carried on a cushioned roller, the punches moving with a peripheral speed equivalent to the circumferential speed of the roller.

The foregoing objects of the invention, and other objects which will become apparent as the description proceeds, are achieved by the provision of apparatus, one embodiment of which is illustrated in the accompanying drawings, as follows:

FIG. 1 is a side elevation of a machine incorporating the principles of the invention;

FIG. 2 is an enlarged fragmentary view, and in cross section of the punch and roll portions of the mechanism;

FIG. 3 is a longitudinal cross sectional view taken substantially on line 3-3 of FIG. 2;

FIG. 4 is a fragmentary view of a portion of the driving mechanism of the apparatus; and

FIG. 5 is a fragmentary view, partly in section, of a punch die which may be used in the apparatus.

In the drawings, the numeral indicates generally a frame or base having a pair of horizontally extending brackets 12 which are laterally spaced apart so as to receive the shaft 14 of a let-off roll 16 of film F. The roll 16 is friction-ally retarded as the film F is pulled therefrom, and this is conveniently achieved by the provision of a small brake drum 18 secured to the shaft 14, and with a strap 20 extending over the drum 18, one end of the strap 20 being secured to the frame at 22, and the other end having a plurality of adjustable quantity weights 24 mounted thereon.

After leaving the let-off roll 16 the film F passes to an idler roll 26 mounted on the base 10 and then passes around a roll 28 covered by a layer of foam or sponge rubber 3%, the roll 28 being carried on a shaft 32 mounted on the base 10. Leaving the roll 28 after passing around a portion of the periphery thereof, for example about half, the film F passes to a wind-up or take-up roll 34 carried on a shaft 36 supported at its end between brackets 38 secured in laterally spaced position on and extending horizontally from the base 10. A motor 40 on the base 10 drives the shaft 36 by way of a V-belt 42 which engages with a pulley 44 carried on the shaft 36.

Fundamentally, there are two ways of driving the apparatus. The first and simplest way is to securedhe pulley 44 to the shaft 36 so that the shaft 36 is driven at a constant rotary speed. In this construction the film F serves to drive the roll 28, but with the speed of the film and that of the roll 28 gradually increasing 3,039,713 Patented June 19, 1962 as the diameter of the film on the wind-up roll 34 builds up. With certain films and thicknesses thereof the change in speed is not objectionable.

However, in the preferred form of the invention and in order to render the operation more uniform, the invention provides for a uniform speed of movement of the film F over the roll 28. This is accomplished in the embodiment of the invention illustrated by having the belt 42 from the motor drive a double V-belt pulley 44a, with the pulley 44a rotating freely on the shaft 36, and with an adjustable friction clutch 46 connecting the pulley 44a to the shaft 36. From the second groove in the pulley 44: a belt 48 extends to a pulley 50 on the shaft 32, all in the manner shown in FIGS. 1 and 4. Thus, the roll 28 is driven at a constant speed, and with the shaft 36 being overdriven through the clutch 46 to provide a constant wind-up tension on the film F and with the slippage of the clutch 46 compensating for the gradually increasing diameter of the Wind-up roll 34.

Now turning to FIGS. 2 and 3 which illustrate in greater detail the punching mechanism, the numeral 52 indicates a shaft mounted between the upright portions of the base 10, and having suitable bearings along its length (not shown). The shaft 52 is positioned parallel to the shaft 32 and has secured to it at a plurality of points along its length, wherever a punching mechanism is desired, an eccentric 54. Each eccentric 54 is surrounded by a low friction type of bushing, such as a nylon ring 56. Each eccentric bushing 56 is surrounded by a crank or strap 58 of spring steel having an arm portion 60 extending towards the roll 28 through a reduced friction guide, for example a nylon plate 62 mounted on a bracket 64 adjustably fastened by bolts 66 extending through adjusting slots 68 in the bracket 64 into a support flange (not shown) on the base 10. The end of the arm 60 is provided with a steel punch 70 of the desired shape, usually round, and with the punch 79 being driven against the surface of the roll 28 upon each rotation of the eccentric 54, but with the punch 76 defining an elliptical path of movement as indicated by the dotted line 72 so that the punch will follow with the film during and after the punching movement until such time as the elliptical path of movement of the punch carries it away from the surface of the roll 28.

By adjusting the position of the fulcrum or bearing plate 62 toward or from the roll 28 by means of the bolts 66 the size of the elliptical path 72 can be changed and specifically the speed of movement of the punch 7! in relation to the surface of the roll 28 can be adjusted so as to make these speeds approximately the same and avoid any tearing of the film.

The shaft 52 carrying the eccentrics 54 is driven at a constant speed with respect to the shaft 32 carrying the roller 28, regardless of how the shaft 32 is driven. The driving of shaft 52' is conveniently accomplished by the provision of a belt 74 extending between a pulley 76 on the end of the shaft 52 and a pulley on the shaft 32. If the shaft 32 is driven by the pulley 59 and belt 48 the pulley 50 can be made a double groove pulley to also receive the belt 74. The center line of the shaft 52 is preferably positioned slightly below the center line of the roll 28 in order to obtain the best impact type punching action. The eccentrics 54 and nylon bushings 56 are usually held against relative axial movement in relation to each other by means of collars 80 secured to the shaft 32 on each side of the eccentric 54.

It is believed that the operation of the apparatus will be understood from the foregoing description. Sufiice it to say here that the film P is pulled from the let-go roll 16 to the wind-up roll 34 at a relatively high rate of speed, this usually being at least several hundred feet per minute and normally approaching 1000 or more feet per minute, and with the roll 23 being driven at a constant speed from motor 40 or being driven by the passage of the film thereover. In either event, the film is carried on the roll 28 under a considerable tension which is adjustable by means of the braking weights 24. Rotation of the roll 28 simultaneously rotates shaft 52 to drive the punches 7 against the film carried on the roll 28 with a very considerable impact force followed by the punch moving with the film and roll surface through an arc of between about five and about twenty degrees, the foam or sponge rubber layer 3% of the roll yielding to allow this movement. It has been found that giving the punch 70 a relatively high velocity and impact in its movement against the tensioned film materially improves the punching action of the mechanism. The punch 7 may be made in the form illustrated in FIG. so that any perforations punched out of the film are worked back through the gradually enlarging hole 82 in the punch and discharged into a tray 84 carried on the base 10.

The spacing between successive punches in the film is dependent, of course, upon the speed at which the shaft 52 is driven in relation to the speed of the shaft 32, and this can be conveniently changed by making the pulleys 76 and 50 of the apparatus of multiple groove and varying diameter type with the belt 74 being changed from one set of grooves to another, as is usual in a Woodworking lathe or the like.

While in accord with the patent statutes one best known embodiment of the invention has been illustrated and described in detail, it is to be particularly understood that the scope of the invention is defined in the appended claims.

What is claimed is:

1. Apparatus for perforating film including a resilient roll, means for moving film at a relatively high speed over an arcuate portion of the rotating roll, and means for moving a punch with a relatively high impact against the film supported on the resilient roll and for concurrently moving the punch in the direction of movement of the film and at substantially the speed thereof, said means moving the punch in substantially a flatly elliptical path and repeatedly into and out of punching engagement with the film.

2. Apparatus for perforating film including a resilient roll, means for moving film at a relatively high speed of at least about 1,000 feet a minute over an arcuate portion of the rotating roll, and means for repeatedly moving a punch with a relatively high impact substantially radially against the film supported on the resilient roll and for thereafter moving the punch in the direction of movement of the film and at substantially the speed thereof.

3. Apparatus for perforating film including a base, an adjustable braked let-go roll for'film on the base, a windup roll on the base, means including a friction clutch for overdriving the wind-up roll, a resilient surface roll on the base positioned so that film passing from the let-go to the wind-up roll passes under tension over an arcuate portion of the resilient surface roll, means for driving the resilient surface roll at a constant speed, a shaft journalled 0n the base parallel to and adjacent the resilient surface roll opposite the arcuately carried film, means for driving the shaft at a speed proportional to the speed of the film, eccentric means on the shaft, spring steel strap means surrounding the eccentric means, said strap means including an integral spring steel arm extending towards the resilient surface'roll, a punch carried by each arm and adapted to engage the film on the resilient roll and an adjustably positioned fulcrum means slidably supporting each arm whereby the punch is moved in an elliptical path and during a portion of that path engages the film in substantially a radial direction and with high impact, and the punch thereafter moving with the film and at substantially the speed thereof during the punching operation.

4. Apparatus for perforating film including a base, a resilient surface roll, means for passing film under tension over an arcuate portion of the resilient surface roll, means for driving the resilient surface roll at a constant speed, a shaft journalled parallel to and adjacent the resilient surface roll opposite the arcuately carried film, means for driving the shaft at a speed proportional to the speed of the film, eccentric means on the shaft, strap means surrounding the eccentric means and including arm means extending towards the resilient surface roll, a punch carried by the arm means and adapted to engage the film on the resilient roll, and an adjustably positioned fulcrum means slidably supporting the arm means whereby the punch is moved in an elliptical path, the punch engaging the film with high impact during the sharply curving portion of the path and moving with the film during the fiatly curving portion of that path.

5. Apparatus for perforating film including a resilient surface roll, means for passing film under tension over an arcuate portion of the resilient surface roll, a shaft journalled parallel to and adjacent the resilient surface roll opposite the arcuately carried film, means for driving the shaft at a speed proportional to the speed of the film, eccentric means on the shaft, strap means surrounding the eccentric means, said strap means including arm means extending towards the resilient surface roll, punch means carried by the arm means and adapted to engage the film on the resilient roll, and an adjustably positioned fulcrum means slidably supporting the arm means whereby the punch means is moved in a relatively flat elliptical path, the punch engaging the film with high impact during the sharply curving portion of the path and moving with the film during the flatly curving portion of that path.

References Cited in the file of this patent UNITED STATES PATENTS 1,768,070 Johnstone June 24, 1930 1,779,562 'Scusa Oct. 28, 1930 1,967,202 Dalton July 17, 1934- 2,261,007 Talbot Oct. 28, 1941 2,369,253 Robinson et al. Febal3, 1945 2,800,179 Munchbaeh July 23, 1957 2,854,077 Novak et 31.0". Sept. 30, 1 958 FOREIGN PATENTS 1,043,906 Germany Nov. 13, 1958 

